HYDRAULIC CIRCUIT FOR FRONT DOZER

PROBLEM TO BE SOLVED: To suppress the temporary stop of a cylinder device when grounding a blade and floating front wheels in a work vehicle mounted with a front dozer.SOLUTION: A hydraulic circuit for the front dozer includes a cylinder device 4 to be expanded and contracted in order to swing the blade of the front dozer to the work vehicle, and a switching valve 9. The switching valve 9 has ports P1-P3. The port P1 is connected through a first distribution path W1 to a pressure chamber S1 of the cylinder device 4. The port P2 is connected through a second distribution path W2 to a pressure chamber S2 of the cylinder device 4. The port P3 is connected through a third distribution path W3 to a discharge port of a pump P. The switching valve 9 switchably has a first section C1, a second section C2 and a third section C3. The third section C3 interconnects the first-third distribution paths W1-W3.